Proc GEMMOD
proc genmod data= ;
class ;
model y = x / dist= link= type3 ;
repeated subject= / corr= type= ;
lsmeans x / diff=control ('ref') cl adjust=Dunnett(or tukey);
run;
| distribution | link function | note |
|---|---|---|
| normal | identity | continuous dependent variable, mean difference |
| binomial | log | risk ratio from exponentiation of the parameter estimate |
| binomial | logit | odds ratio |
| poisson | log | risk ratio from exponentiation of the parameter estimate; used for robust error estimate with repeated subject statement |
Parameters estimated with maximum likelihood methods.
Repeated statement: specifies the covariance structure of multivariate responses and iterative fitting algorithm for GEE model fitting.
- Subject: Responses from different subjects are assumed to be statistically independent, and responses within subjects are assumed to be correlated. Variables used in defining the subject-effect must be listed in the CLASS statement. The input data set does not need to be sorted by subject.
- Corr= specifies the correlation structure: Un unstructured; IND independent.